Aircraft instrument operation trainer

ABSTRACT

On one side of a portable case are mounted aircraft instruments, a control wheel and a throttle to simulate the instrument panel and controls of an airplane. The control wheel and throttle are movable and interconnected by compound lever mechanism which is connected to actuate the tachometer, the airspeed indicator, the artificial horizon elevationally, the rate-of-climb indicator and the altimeter. The control wheel is connected independently of the compound lever to actuate the turn indicator, the tilting of the artificial horizon, the directional gyro, a VHF omnirange indicator, a course recorder and an automatic direction finder.

United States Patent 5] Nov. 14, 1972 Cramer [54] AIRCRAFT INSTRUIVIENTOPERATION TRAINER [72] Inventor: Harry E. Cramer, Seattle, Wash.

[73] Assignee: Cramer Instrument Flight School, Inc., Seattle, Wash.

[22] Filed: June 17, 1970 [21] Appl. No.: 46,871

[52] US. Cl. ..35/12 W [51] Int. Cl. ..G09b 9/08 [58] FieldofSearch.........35/12F, 12 L, 12 W, 12 D, 35/102 [56] References CitedUNITED STATES PATENTS 3,378,938 4/1968 Frasca ..35/l2 W 2,336,71112/1943 Barber......................35/12 W 3,534,486 10/1970 Frasca eta1 ..35/l2 L Link, Jr. ..35/l0.2 Weitzman et a1. ..35/l2 D ABSTRACT Onone side of a portable case are mounted aircraft instruments, a controlwheel and a throttle to simulate the instrument panel and controls of anairplane. The control wheel and throttle are movable and intercom nectedby compound lever mechanism which is connected to actuate thetachometer, the airspeed indicator, the artificial horizonelevationally, the rate-ofclimb indicator and the altimeter. The controlwheel is connected independently of the compound lever to actuate theturn indicator, the tilting of the artificial horizon, the directionalgyro, a VHF omnirange indicator, a course recorder and an automaticdirection finder.

14 Claims, 20 Drawing Figures PATENTEDNM 14 m2 SHEEI 2 BF 9 INVENTOR.MAR/Q54 E. KWAMA'E kw M P'A'TE'N'TEDunv W912 3.702.504

sum 3 0F 9 "I VIIIIIIIIIIIIIIIIIIIIIIIJ ull INVENTOR. IVAZFV mew/ E gwmwA ffdF/V Fy FATENTEDunv 14 m2 SHEU 5 OF 9 INVENTOR. MAP/PW 1:. (564/452ATTO/P/VEV PHEN'TEDunv 14 m2 SHEET 6 [IF 9 INVENTOR. f/AKF/ 5: [2 14/755 harm W PATENTEH luv 14 I97? SHEU 9 OF 9 94 f7-77777777f f/777777/7"INVENTOR. AMPFK .5 (24/ /52 bur/$1M AIRCRAFT INSTRUMENT OPERATIONTRAINER The aircraft instrument operation trainer of the presentinvention is to be used in the classroom for illustrating the techniqueof aircraft instrumentation operation and use in a qualitative mannerrather than in a quantitative manner. Consequently, the principles ofoperation are demonstrated instead of being concerned with preciseduplication of actual flight conditions.

A principal object of the invention is to provide an economical trainerwhich is compact and light so as to be portable, yet which issufficiently realistic so that a pilot can benefit from his operation ofthe trainer nearly to the same extent as in operating an airplane as faras the principles of operation are concerned.

In providing a realistic training experience for the pilot, it is anobject to provide controls and instruments which closely simulate theactual controls and instruments in a light airplane and which controlsand instruments are interconnected so that movement of the flight andengine controls to simulate a flight maneuver will effect movement ofthe instruments in a manner corresponding to the instrument movementwhich would result from the performance of an airplane maneuver producedby such control movement.

Another object is to provide a recorder for recording a simulated flightpath of the general character which would be followed by an airplane ifits controls were manipulated in the manner that the trainer controlsare manipulated. In particular, it is an object to coordinate turningmovement of the control wheel with the course recorder so that therecorder will record the course which would be steered by the airplane.In this connection, it is a further object to provide acourse-indicating instrument for use by an instructor.

It is also an object to provide an aircraft instrument operation trainerhaving the capabilities mentioned above which is principally ofmechanical construction and does not use electronic controls, so as tocurtail the initial cost of the apparatus and to minimize maintenanceexpense.

FIG. I is a top perspective of the portable aircraft instrumentoperation trainer in carrying condition;

FIG. 2 is a top front perspective of the trainer set up forinstructional operation;

FIG. 3 is a front elevation of the trainer prepared for instructionaloperation;

FIG. 4 is a rear top perspective of the chassis of the trainer, and

FIG. 5 is an enlarged rear top perspective of one end portion of suchchassis;

FIGS. 6 to 12, inclusive, are somewhat diagrammatic plans of the portionof the chassis shown in FIG. 5, illustrating components in differentoperative relationships, and

FIG. 13 is a rear top perspective of the end portion of the chassis likethat shown in FIG. 5, but with parts in an operative relationshipdifierent from the relationships illustrated in FIGS. 5 to 12,inclusive,

FIG. 14 is a rear top perspective of the left end portion of the chassisas seen in FIG. 4 on an enlarged scale;

FIGS. 15 and 16 are plans of the same end portion of the chassis andFIG. I7 is a section taken on line 17-17 of FIG. 15;

FIG. 18 is a rear top perspective of a portion of the mechanismillustrated in FIG. 14 showing an alternate form of apparatus and havingparts broken away;

FIG. 19 is a plan of a portion of the mechanism shown in FIG. 18, and

FIG. 20 is a front elevation of a portion of the mechanism viewed fromline 20-20 of FIG. 19.

A principal advantage of the flight trainer of the present invention isits portability while still giving the general impression of an actualairplane instrument panel. The trainer is portable because the mechanismis contained in a casing 1 small enough and light enough to be carriedeasily by a handle 2. The side of the case opposite that to which thehandle is attached is closed by a cover 2'. Such side of the caseconstitutes the instrument panel 1', having in it an opening 1"affording access to a portion of the interior of the casing. The inside2" of the cover 2 when the cover is in the open position of FIG. 2provides a surface for display of problem-solving data, or a holder fora written flight plan or navigational problem. Such surface may providean erasible drawing area and a surface of magnetic material to whichmagnetized airplane models may be applied.

Supported from the casing l is a control wheel 3 mounted on a controlshaft 4 which can be reciprocated and rotated by a student pilot usingthe trainer. Alongside the control wheel, the casing carries thethrottle 5 which can be reciprocated to simulate the control of enginespeed. A trim control wheel 6 may be rotated to simulate correction forelevational control of the aircraft. It may be connected through springmeans to the control shaft 4 for varying the force required to beexerted on the control wheel to move it forward or rearward.

The instruments mounted on the instrument panel face 1 of the case areeither actual airplane instruments or closely simulate such instruments.The top row of instruments as seen in FIG. 3 are, from left to right, anairspeed indicator 7, an artificial horizon 8, an altimeter 9, a veryhigh frequency omnirange indicator (VCR) or instrument landing systemindicator (ILS) l0 and and instructors VOR-ILS monitor 1 1.

In the lower row of instruments, designated from left to right as seenin FIG. 3, are a turn indicator 12, a directional gyro 13 for indicatingheading, a rate-ofclimb indicator or climb indicator or vertical speedindicator 14, an automatic direction finder (ADF) l5 and a tachometer16. Simulated controls of various types may be arranged along the bottomof the panel including an ignition switch 17, which can function as themaster switch for the electrical components of the trainer, a carburetorheat control 18 and a fuel mixture control 19. A localizer selector 20and a glide-slope selector 21 may be provided to be manipulated forindicating recognition that the VOR-ILS indicator is to be used fordifferent functions.

While the normal aircraft controls include separate controls forcontrolling the rudder and the ailerons of the airplane, it iselementary that movement of the elevator controls and aileron controlsmust be coordinated by the pilot in order to accomplish properturnand-bank maneuvers. From a navigational point of view, the importantconsideration is the degree and duration of the turning of the airplane.Consequently, for instrument operation training purposes, the turning ofthe control wheel 3 is adequate to simulate a turning maneuver of theairplane.

in general, therefore, the trainer serves two functions; first, toindicate to the student pilot the action produced on the instruments bythe airplane maneuvers effected by certain manipulations of the flightand engine controls, and second, to enable the student pilot to executenavigational problems in principle by manipulation of the flightcontrols for simulating a predetermined flight path of the airplane.While the present trainer is capable of both functions, av similartrainer could be constructed to provide only one or the other of suchfunctions.

First, with respect to the function of the instruments reflecting theeffect on the airplane produced by manipulation of the controls, it isknown that independent operation of the control wheel and of thethrottle can produce corresponding effects on the attitude of theairplane. Thus, if the control wheel 3 is pulled rearward, simulatingupward deflection of the elevators, without movement of the throttle,the airspeed of the airplane should be reduced, the rate of climb shouldincrease and the horizon should drop. The same general phenomena shouldoccur with respect to increase in rate of climb and dropping of thehorizon if the throttle 5 is pushed forward, but the airspeed shouldincrease instead of decreasing.

Conversely, if the control wheel 3 is pushed forward, representingdownward deflection of the elevators, without the throttle 5 being movedfrom normal cruising position, the airspeed should increase, the rate ofclimb should decrease and the horizon should rise. On the other hand, ifthe throttle 5 is pulled rearward while the control wheel 3 remains innormal level flight position, the rate of climb should decrease and thehorizon should rise, but the airspeed should be reduced instead ofincreasing.

It is therefore evident that if the airspeed indicator 7, therate-of-climb indicator 14 and the artificial horizon 8 are to reflectmaneuvers of the airplane accomplished by forward or rearward movementof the control wheel 3 and/or forward or rearward movement of thethrottle 5, the movements of such control wheel and throttle must becoordinated in the activation of the airspeed indicator, therate-of-climb indicator and the artificial horizon. Movements of thesetwo control elements must also be coordinated if the altimeter 9 is toreflect assumed changed in altitude resulting from an indicated positiveor negative rate of climb. To accomplish coordinated influence of themovements of the control wheel 3 and of the throttle 5 on suchinstruments, such control elements are mechanically interconnected.

The shaft 4 on which the control wheel 3 is mounted is both reciprocableand rotatable by corresponding movement of the control wheel. Such shaftis mounted in a bearing on the control panel 1 and in a bearing 22spaced a substantial distance forwardly of the control panel. A flightcontrol-actuating cable 23 has one end connected to the forward end ofthe control wheel shaft. This cable extends from such shaft around guidepulleys 24 and 25 mounted on the chassis to turn about upright axes andis return bent around a guide pulley 26 mounted on the trainer chassisto rotate about a horizontal axis. The other end of the control cable issecured to one end of the tensioning spring 27, the other end of whichis secured to the spring anchor 28.

The central portion of a main control-actuating lever 29 is mounted on apivot 30 guiding the lever to swing about an upright axis. The length ofsuch lever extends transversely of the control wheel shaft 4 andgenerally parallel to the instrument panel 1'. Such pivot divides thelever into an input arm 31 at one side of the pivot and an output arm 32at the opposite side of the pivot. The flight control cable 23 issecured to the end of the main lever input arm remote from pivot 30 by aconnection 33.

The main control-actuating lever 29 is part of a compound lever systemincluding an auxiliary lever 34 which is mounted by the pivot 35 on aportion of the main lever output arm 32 remote from the pivot 30. Suchauxiliary lever is divided by pivot 35 into an output arm 36 overlappingthe main lever and an input arm 37 projecting beyond the output arm 32of the main lever and connected to the throttle 5. Such connection, asshown best in FIGS. 5 and 13, includes a pin 38 carried by the throttle5 which is received in a slot 39, the length of which extends lengthwiseof the auxiliary lever input arm 37.

The compound lever mechanism is preferably arranged so that when thecontrol wheel 3 and the throttle S are disposed in positioncorresponding to normal level cruising flight, as shown in FIG. 6, themain control actuating lever 29 and the auxiliary lever 34 will bedisposed in substantially parallel overlying registry generally parallelto the instrument panel 1' although not necessarily precisely parallelto it. The throttle 5 is mounted for lengthwise reciprocation in abearing mounted on the instrument panel and a bearing 40 spaced forwardfrom the instrument panel so that lengthwise reciprocation of thethrottle will effect movement of the pin 39 connecting the throttle andthe auxiliary lever 34 in a direction transversely of the length of suchlever.

As mentioned above, reciprocation of the control wheel 3 and throttle 5cooperate to alter the airspeed, the rate of climb and the elevation ofthe airplane symbol relative to the horizon. Consequently, the compoundlever system 29, 34 must be connected to the airspeed indicator 7, therate-of-climb indicator l4 and the artificial horizon 8. In addition,movement of the lever system must be arranged to drive the altimeter 9up or down in accordance with the actuation of the rate-of-climbindicator 14.

The connections between the compound lever system, the airspeedindicator, the artificial horizon, the rate-of-climb indicator and thealtimeter are shown best in FIGS. 4 to 13, inclusive. The airspeedindicator drive link 41 has one end connected to a lug 42 mounted on thearm 36 of the auxiliary lever 34. The opposite end of this link isconnected to an arm 43 mounted on the airspeed-indicator actuator drivesleeve 44. Such drive sleeve is supported by the mounting rod 45extending through it.

Such airspeed-indicator actuator drive sleeve 44 carries an output lever46, the swinging end of which is connected to a drive belt 47 passingaround the drive pulley 48 of the airspeed indicator. Such drive belt isheld taut by its end remote from lever 46 being connected to an anchoredtensioning spring 49. Such spring has sufficient flexibility to stretchfor enabling the drive belt 47 to move lengthwise for turning theairspeed indicator drive pulley 48 as the lever 46 swings.

The airplane symbol slide of the artificial horizon is movedelevationally by the vertically reciprocable actuator 50 spring-pressedupwardly and movable downwardly by a pull on the artificial horizoncontrol cable 51. The other end of this control cable is connected by alug 52 to the arm 31 of the lever 29 at a lo cation close to the pivot30 so that, as such main lever swings, the reciprocable slide actuator50 will move elevationally only a small amount.

The rate-of-climb indicator 14 is actuated by lengthwise reciprocationof a link 53 one end of which is connected to a lug 54 mounted on thearm 37 of the auxiliary lever 34. The other end of this link isconnected to one arm of a bell crank 55 carried by a mounting sleeve 56that encircles and is supported by the stationary mounting rod 45. Theother arm of such bell crank is connected to one end of a drive belt 57that extends around the rate-of-climb indicator drive pulley 58. Theother end of such drive belt is connected to an anchoringbelt-tensioning spring 59.

FIGS. 5 to 12 illustrate the control wheel 3 and throttle 5 in variousrelatively reciprocated relationships producing a variety of effects onthe compound-lever mechanism and in turn on the airspeed indicator,rateof-climb indicator and artificial horizon. First, considering theeffect of the reciprocation of the flight control wheel 3 on thecompound lever system, FIGS. 6, 7 and 8 show the throttle 5 in the sameposition of adjustment in each instance, which may be assumed to be theadjusted position corresponding to cruising speed. In FIG. 6, thecontrol wheel 3 is positioned so that the airplane is assumed to beflying horizontally. The two levers 29 and 34 are in overlying alignmentor registry and the links 41 and 53 and the cable 51 are located so thatthe airspeed indicator 7 indicates cruising speed, the rate-of-climbindicator 14 indicates zero rate of climb or descent and the artificialhorizon 8 indicates level flight.

If the control wheel 3 is pushed forward somewhat from the position ofFIG. 6 to that of FIG. 7, representing downward swinging of theelevator, the spring 27 in maintaining tension on the control-actuatingcable 23 shortens and pulls the attachment 33 of the control cable tothe arm 31 of lever 29 to swing such lever from the position of FIG. 6to that of FIG. 7. Such swinging moves the lever-connecting pivot 35from the position of FIG. 6 to that of FIG. 7, which swings the lever 34about the throttle pin 39 as an axis. The airspeed indicator drive link41 and the rate-of-climb indicator drive link 53 are both reciprocatedlengthwise rearward toward the instrument panel 1', the link 41 beingshifted a distance greater than the link 53.

Such rearward shifting of link 41 will swing arm 43 toward theinstrument panel to rotate sleeve 44 for swinging arm 46 downward whichpulls drive belt 47 to rotate the airspeed indicator drive pulley 48 ina clockwise direction as viewed from the front of the in strument panel.Such rotation of the pulley will cause the airspeed indicator needle toindicate an increased air speed, which would result from the descent ofan airplane that would be induced by downward swinging of the elevatorseffected by moving control wheel 3 forward.

Movement of the rate-of-climb indicator drive link 53 lengthwiserearward will pull the drive belt 57 to rotate drive pulley 58 in thecounterclockwise direction, thus indicating a reduced rate of climb or,in this instance, an increased rate of descent. The pull on controlcable 51 which actuates the artificial horizon slide will move theactuator 50 to indicate an elevation of the horizon or descendingattitude of the airplane.

If instead of the control wheel 3 being pushed forward from the positionof FIG. 6 to the position of FIG. 7 such wheel is pulled rearward to theposition of F IG. 8, again without changing the position of the throttle5, the lever 29 will be deflected relative to the lever 34 as seen inFIG. 8, that is, in the direction opposite that in which it wasdisplaced in FIG. 7. The efi'ect of such control wheel movement will beto move the airspeed indicator drive link 41 lengthwise forward forswinging levers 43 and 46 to move drive belt 47 for turning the airspeedindicator drive pulley 48 in a counterclockwise direction to indicate areduction in speed. Such reduction in speed would be correlated with themovement of the control wheel simulating a climb.

The link 53 would also be moved lengthwise and forward by swinging ofauxiliary lever 34 about the throttle connecting pin 39, but to a lesserdegree. Such forward movement would swing the belt crank 55 forrelieving the tension on the drive belt 57 so that the rateof-climbindicator pulley 58 would turn in a clockwise direction as seen from thefront of the instrument panel, indicating an increased rate of climb.

The swinging of arm 31 of the lever 29 from the position of FIG. 6 tothat of FIG. 8 would relieve the tension on the artificial horizonactuating cable 51 so that the actuator 50 would rise, indicating alowering of the horizon.

In FIGS. 9 and 10, the control wheel 3 has been left in the levelcruising flight position of FIG. 6, and in FIG. 9 the throttle 5 hasbeen advanced by pushing it forward, while in FIG. 10 the throttle hasbeen retarded by pulling it rearward from the position of cruising speedshown in FIG. 6. The forward movement of the throttle to the position ofFIG. 9 will swing auxiliary lever 34 relative to the main lever 29,which remains stationary, to move link 41 lengthwise rearward. Suchlever movement swings the arms 43 and 46 for increasing the tension onairspeed indicator drive belt 47 which will turn the drive pulley 48 ina clockwise direction to indicate an increase in air speed. Instead ofthe link 53 also being moved lengthwise rearward, however, such linkwill be moved forward away from the instrument panel. Such movement willdecrease the tension of spring 59 on rate-of-climb indicator drive belt57 so that the drive belt 57 will move to turn pulley 58 in a clockwisedirection as seen from the front of the instrument panel, indicating anincrease in the rate of climb.

It will be observed from a comparison of FIGS. 7 and 9 that, while theairspeed is indicated as being increased both by movement of the controlwheel forward and by movement of the throttle forward, the rate of climbis decreased by forward movement of the control wheel while beingincreased by forward movement of the throttle in conjunction with anincrease in air speed in both instances.

In FIG. 10, rearward movement of the throttle 5 to simulate a reductionin power has swung lever 34 on its pivot 35 relative to lever 29 to movethe air speed indicator drive link 4] forward and the rate-of-climbindicator drive link 53 rearward. Such forward movement of the air speedindicator drive link has swung arms 43 and 46 so as to relieve thetension on the drive belt 47 and caused the drive pulley 48 to rotate ina counterclockwise direction as seen from the front of the instrumentpanel, indicating a reduction in air speed. The rearward movement oflink 53 has swung bell crank 55 to increase the tension on therate-ofclimb indicator drive belt 57 to effect turning of the drivepulley 58 in a counterclockwise direction, indicating a reduction in therate of climb.

Comparing the action of the compound linkage in FIG. 8 and 10, it willbe seen that rearward movement of the control wheel and rearwardmovement of the throttle both effect forward movement of the airspeedindicator drive link 41 to indicate a decrease in air speed, but whenthe control wheel is moved rearward the rate-of-climb indicator link ismoved forward to produce an indication of increased rate of climb,whereas when the throttle is moved rearward, the rateof-climb indicatordrive link 53 will also be moved rearward to effect an indication of areduction in rate-oi climb.

In actual flight maneuvers, the control wheel and the throttle arefrequently moved at the same time. Thus, to perform a glide, the controlwheel will be moved forward from the level flight cruising condition ofFIG. 6 while the throttle will be moved rearward from the cruising powerposition, so as to be disposed in the rela tionship shown in FIG. 11. Bysuch manipulation of the controls, the levers 29 and 34 may be turnedconjointly about the pivot 30 into the positions shown in FIG. 11. Bysuch movement, both the airspeed indicator drive link 41 and therate-of-climb indicator drive link 53 will have been shifted lengthwiserearwardly, but in this instance, the link 53 will be shifted to agreater extent than the link 41 instead of, as in FIG. 7, the link 41being shifted to a greater extent than the link 43.

As in the maneuver of FIG. 7, rearward movement of link 41 will swingarms 43 and 46 to move the drive belt 47 for turning the pulley 48 toindicate an increase in air speed, but such increase will be much lessthan in the situation of FIG. 7. Also, rearward movement of link 53 willswing bell crank 55 to pull drive belt 57 for turning pulley 58 toindicate a decrease in rate of climb, that is, a descent. In thisinstance, however, the rate of descent indicated will be much greaterthan that indicated by the condition of FIG. 7.

FIG. 12 illustrates the opposite type of maneuver from that illustratedby FIG. 11. In this instance, the control wheel 3 has been pulledrearward from the position of FIG. 6 and the throttle has been pushedforward, simulating a power climb. In this instance, the two levers 29and 34 again are shown as being in superposed registry, but swung aboutthe pivot 30 of the compound lever system from the position of FIG. 6 inthe direction opposite to that in which the lever system is shown tohave been swung in FIG. 11. By this manipulation, both the airspeedindicator drive link 41 and the rate-of-climb indicator drive link 53have been shifted lengthwise forward and the link 53 has been shifted toa greater extent than the link 41, instead of vice versa as shown inFIG. 8.

Again, the forward shifting of link 41 will swing levers 43 and 46 todecrease the tension in drive belt 47 for turning the airspeed indicatordrive pulley 48 so that the airspeed indicator will show a reduced airspeed. Such reduction in air speed will, however, be less than thatindicated when the control wheel 3 is moved rearward without thethrottle being pushed forward. The greater forward movement of the link53, however, will swing the bell crank 55 for reducing the tension onthe rate-of-climb indicator drive belt 57 a greater amount so that thepulley 58 will be turned farther in a clockwise direction to indicate agreater increase in the rate of climb.

The airspeed indicator 7, the artificial horizon 8 and the rate-of-climbindicator 14, the operation of which has been thus far described, allindicate instantaneous conditions. If a climb or glide is continued,however, the altitude of the aircraft will be altered substantially andthe altimeter 9 is actuated to indicate this circumstance. To accomplishthis operation, a double-acting altimeter-energizing switch 60 islocated for actuation by a rotative cam 61 turned by swinging of thebell crank 55 by forward or rearward movement of the drive link 53.

The double-acting switch 60 is electrically connected to the altimeterdrive motor 62 shown in FIG. 14. The armature of this motor can rotatein one direction or the other to swing crank 63 correspondingly fordriving the speed-reducing belt combination 64 to turn die altimeterdrive pulley 65. Rotation of the motor 62 in one direction willtherefore progressively increase the reading of the altimeter 9 whereasrotation of the motor in the opposite direction will progressivelydecrease the reading of the altimeter.

When the control wheel 3 and the throttle 5 are held in a position suchthat the rate of climb indicator 14 indicates an ascent or a descent foran appreciable period of time, the altimeter 9 will be driven toindicate a corresponding accumulated increase or decrease in altitude.Such altitude change indication is qualitative rather than preciselyquantitative because the switch 60 is simply of the make-and-break typeand is not a rheostat. When switch-actuating cam 61 is turned far enoughto close a circuit through switch 60 the altimeter-driving motor 62 willbegin to operate, but it will operate at a constant speed irrespectiveof the extent of movement of the control wheel 3 and/or the throttle 5.

It will be understood that the conditions described with reference toFIGS. 6 to 12, inclusive, are only representative conditions and thecontrol wheel 3 and throttle 5 can be moved separately or conjointlydifferent amounts. Also, manipulation of the control wheel 3 has beendescribed as only forward or rearward without being turned, but suchcontrol wheel may be turned either independently of or in conjunctionwith a forward or rearward movement of the wheel.

FIG. 13 illustrates the condition in which the control wheel 3 has beenturned counterclockwise from the straight flight condition representedby FIG. 5, which would simulate a turn to port, without the controlwheel being moved forward or rearward. Such manipulation of the controlwheel rotates the control wheel shaft 4 to tilt posts 66 projectingradially upward from such shaft. The upper ends of these posts areconnected by and support a sleeve 67, through which extends a crankedcontrol rod 68. The crank end of this control rod is connected to aportion of lever 69 spaced from pivot 70 which supports such lever forswinging. This lever in turn is connected to a shorter driven lever 71by a connecting link 72.

The driven lever 71 is mounted for swinging on a drive shaft 73,carrying the needle of the turn indicator 12. Consequently, as the posts66 are tilted by rotation of the control wheel 3, the sleeve 67 isdisplaced orbitally to move the cranked control rod 68 bodily. Suchcontrol rod movement is effected irrespective of the position of forwardor rearward reciprocation of shaft 4 because such reciprocation willslide sleeve 67 freely along rod 68 without displacing it lengthwise.

As the rod 68 is moved orbitally it will swing lever 69 in thecorresponding direction, which in turn will move link 72 to swing lever71 for actuating the turn indicator. Such swinging of lever 69 will alsoeffect rotation of shaft 74 of the artificial horizon 8 by swinging arm75 carried by such shaft, which is connected to the lever 69 by link 76.Rotation of shaft 74 will tilt the artificial horizon line to representbanking of the airplane.

The turn indicator 12 and artificial horizon 8 indicate instantaneousdepartures of the airplane from a straight course. As simulated turningof the airplane is continued, the heading of the airplane will bealtered, and such heading can be recorded on a simulated chart C to plotthe course of the airplane. To accomplish this operation, the swingingof lever 69 through an appreciable angle closes one or the other of therecordercontrolling switches 77 by moving against the control arm of oneswitch or the other the abutment 78 carried by the lever arm 69.

Closing of one or the other of the switches 77 will energize areversible heading motor 79 to rotate in one direction or the other.Such motor rotates an output pulley 80 that drives belt 81 connected toturn pulley 82 mounted on the directional gyro drive shaft 83. Byrotation of such drive shaft, the bearing indicating disk of thedirectional gyro 13 is rotated to indicate change in heading of theairplane as the control wheel 3 is maintained in turned condition in onedirection or the other.

Rotation of the heading motor 79 also drives the recorder-orientationdrive chain 84 which extends around the driving sprocket 85 turned bymotor 79 and the transition-driven sprocket 86 mounted on the swingingend of the primary recorder support arm 87. Such transition sprocket iscoaxial with and drives a pulley 88. This pulley, and a second pulley89, mount the secondary recorder orientation drive belt 90. Pulleys 88and 89 are supported on the secondary support arm 91, which with arm 87forms dogleg linkage.

A shaft 92 journalled in the swinging end of arm 91 carries pulley 89 onits upper portion that will be turned by turning of such pulley. Thelower end of such shaft supports the recorder head 93 in the positionsuch that its marking wheel 94 contacts the chart C at a point inalignment with the rotative axis of the shaft 92.

The recorder head is moved over the chart by rotation of the markingwheel 94 effected by contact of the periphery of the friction drivewheel 95 with the periphery of such marking wheel. Such friction wheelis turned by an electric motor 96 mounted on the recording head. Thismotor is energized whenever the electrical system is energized forrecording a navigational problem either by manipulation of a masterswitch or closing of a switch accomplished by moving the throttle 5forward a predetermined distance to approximate flying speed. The speedof motor 96 does not, however, vary progressively with change in thereading of the airspeed indicator, but normally operates at constantspeed.

If it were desired simply to record on the chart C the course of theairplane resulting from turning the control wheel 3 in one direction orthe other, the upper portion of the mechanism shown in FIGS. 14 to 17,would not be required. It is desirable, however, to actuate very highfrequency omnirange (VOR) and automatic direction finder (ADF)instruments in connection with the recorder.

For this purpose a downwardly-opening guide channel 97 is mounted on thelower end of a shaft 98 to swing with rotation of such shaft. The axisof such shaft extends in vertical registry with the center of the polarchart C, which chart center represents a VOR station location. A knob 99mounted on the upper end of shaft 92 is received snugly, but nottightly, in the channel so that it can move freely along the channel.Such knob can be of anti-friction material, such as of Teflon, or may bea roller if preferred.

If the recorder head 93 is oriented so that its movement is along aradius of the polar chart with which the guide channel 97 registers,such channel will remain stationary. If the recorder head is turned bythe orienting motor 79 so that the movement of the recording head is nolonger radial, the knob 99 will swing the channel 97 and correspondinglyrotate shaft 98 about the axis of such shaft and the chart center. Suchrotation of shaft 98 in turn will rotate the VOR drive pulley 100secured on such shafl to drive belt 101 passing around guide pulleys 102to turn the driven VOR pulley 103. This pulley is mounted on the shaft104 of the monitoring VOR instrument 11 to turn the VOR needle. Pulley105, loosely mounted on shaft 104, is driven by belt 106 which passesaround guide pulleys 107 and 108 to engage a driving pulley 109 mountedon shaft 110 turned by the disk of the students VOR indicator 10. Suchdisk can be adjusted by the student turning the omnibearing selector(OBS) knob 10.

As the channel 97 is swung by movement of the recorder head, the needleof the monitoring VOR instrument 11 will be turned correspondingly toindicate a change in bearing between the location of the airplane andthe VOR transmitting station.

To make the student's VOR instrument 10 more realistic, the coursedeviation indicator (CDl) needle can be movable by a control knob on theinstrument panel. Rotation of such knob exerts a pull on the drive line1 11, shown in FIG. 14, which is tensioned by spring 112. Such line isconnected to the arm 1 13 connected to the needle which is carried bythe mounting 114. Such instruments can also be indicative of aninstrument landing system (lLS) instrument by having a swingable,generally horizontal needle to indicate the landing glide slope.Alternatively such needle may be shifted to indicate to" or from" zonesof the VOR. Such needle can be swung by rotation of another knob on theinstrument panel connected to the drive line 1 15 also shown in FIG. 14.This line is tensioned by spring 116 and is connected to the arm 1 17for the glide slope needle supported by mounting 1 18.

As mentioned above, the motor 96, which drives the recorder head 93 is aconstant speed motor, but a tachometer 16 can be provided on theinstrument panel to reflect the relationship between presumed enginespeed and air speed. As shown in FIG. 4, such tachometer is driven by adrive belt 119 connected to the end of lever 34 adjacent to the throttle5. Such drive belt passes over idler pulleys 120 and 121 and around thetachometer drive pulley 122 to the belt-tensioning spring 123.

In addition to driving the VCR instruments, an automatic directionfinder (ADF) can be driven from shaft 98. For this purpose the casing ofthe ADF drive motor 124 is mounted on the shaft 98 to be turned with theshaft. The output shaft 125 of such motor and shaft 98 are rotativelymounted in a bracket 126 mounted on the chassis.

As shown best in FIG. 14, on the output shaft 125 is mounted the ADFdrive pulley which drives belt 128 passing over guide pulleys 129 todrive the driven pulley 130 mounted on the ADF operating shaft 131. Suchshaft carries the ADF needle. Consequently shaft 131 and the ADF needlewill be turned as the result both of the swinging of the channel 97 andthe energization of motor 124 which is connected in parallel with themotor 79. The ADF setting knob 15' carries the pulley 132 which drivesbelt 133 to turn the ADF disk-adjusting pulley 134.

In the modified apparatus shown in FIGS. 17 through 20, the VCRindicator or localizer needle 135 is driven by the recorder mechanisminstead of simply being swingable manually for demonstration purposes.The needle is suspended from its mounting shaft 136 at the top of theVCR indicator, and such shaft is support for rotation by the bracket137. The lower end of the needle-swinging lever 138, depending fromshaft 136, is received in the lever-swinging yoke 139 mounted on one endof a bell crank 140. Another yoke fork 141 straddles the flange 142projecting radially from a sleeve 143, which sleeve is mounted on shaft144 attached to the omnibearing selector (OBS) knob 10'.

The shaft 144 and needle-actuating flange 142 are interconnected forconjoint rotation but relative axial sliding by a radial pin 145projecting from the shaft being slidably received in a slot 146 in thesleeve 143. Such sleeve also carries a radially projecting arm on whicha cam-follower roller 147 is mounted to engage the face of a disk 148disposed in a plane inclined relative to the axis of shaft 144 andsleeve 143.

The inclined disk 148 is carried by a sleeve 149 also mounted on shaft144, but independent of sleeve 143. Sleeve 149 is rotatable relative toshaft 144, but cannot move axially along such shaft. The carn roller 147is held in contact with the face of the inclined cam disk 148 by ahelical compression spring 150 engaged between the flange 142 and anabutment on shaft 144. Such abutment is illustrated in FIGS. 18 and aspulley 151 secured to the shaft.

Relative rotational movement between the cam 148 and the cam-followerroller 147 will effect movement of sleeve 143 and its flange 142lengthwise of shaft 144. Such movement will cause the flange to engagethe yoke 141 of bell crank 140 to swing such bell crank and,consequently, to cause yoke 139 on its other arm to swing theneedle-swinging lever 138. Such relative rotation of the cam and camfollower may be accomplished either by rotation of the cam or byrotation of sleeve 143 or both.

The belt 101 is connected to the recorder head driven channel 97. As thebearing from the aircraft to the station changes the channel 97 will beswung, and the belt 101 will drive the sleeve 149 and cam disk 148correspondingly because pulley 103 is flxed on sleeve 149. Rotation ofthe cam disk will effect movement of cam follower 147, sleeve 143 andflange 142 along shaft 144 to swing bell crank and the VCR needle. TheOBS knob can be turned to turn sleeve 143 for moving the cam follower inthe same direction that the disk 48 was turned so that the flange 142will be returned to its null position and needle 135 will return to itscenter position shown in H0. 19.

The VOR disk can be set by turning the OBS knob 10' which will turn thedrive pulley 151 for driving belt 152 engaging the driven pulley 153.This driven pulley is rotatably connected to the disk 153'.

in order to indicate the station orientation relative to the aircraft,the instrument panel 1' has in it a window through which the word to" orthe word from" on a swingable flag 155 may be observed. Such flag iscarried by a shaft 156 supported by a bracket 157. The cranked end ofsuch shaft extends alongside a substantially semicircular earn 158engageable by a cam-follower roller 159 on the cranked end of shaft 156.Such cam-follower roller is held in engagement with the cam by a torsionspring 160 reacting from the supporting bracket 157.

When the simulated flight path being recorded on the chart C is movingtoward the center of the chart the cam 158 will be in a rotativeposition such that the cam-follower roller 159 bears on the flat side ofthe cam as shown in FIGS. 18 and 20, so that the word to" will beobserved through the window 154. When the recorder reaches the center ofthe polar chart it is necessary for the operator to reach through theopening 1" in the instrument panel and swing the channel 97 through189". Such reversal will drive the belt 101 to rotate cam 158 so thatthe cam-follower roller 159 will ride onto the semicircular side of thecam causing the shaft 156 to be rotated to raise the flag 155 into theposition shown in FIG. 19, where the word from" appears in the window154. Continued progress along the simulated course will then be in adirection away from the VQR station location at the center of the chart.

Additional refinements may be included in the apparatus if desired. Onesuch refinement includes the switch 161 shown in FIGS. 4 and 5 having anarm engageable with a cam 162 mounted on sleeve 44, which drives theairspeed indicator 7. Such cam can be coordinated with the airspeedindicator so that if the needle of the airspeed indicator turns in acounterclockwise direction beyond a predetermined position correspondingto assumed stalling speed of the airplane, the switch 161 will be closedto energize a suitable audible or visual warning.

in order to maintain accurate correlation between the variousinstruments and their actuating mechanisms, it is desired that thevarious drive belts be of a positive drive type, such as toothed beltsengaging tooth pulleys. Also, it will be understood that a suitablesource of power will be provided for energizing warning signals,providing illumination where desired and energizing drive motorsdescribed.

lclaim:

1. An aircraft instrument operation trainer comprising a simulatedflight control, a simulated engine control, a flight conditionindicating instrument, and drive means connected to drive saidinstrument and including a main lever connected to said simulated flightcontrol and an auxiliary lever pivotally mounted on one arm of said mainlever at a location spaced from the rotative axis of said main lever,said auxiliary lever being connected to said simulated engine controlfor actuation of said instrument both by said simulated flight controland by said simulated engine control.

2. The trainer defined in claim 1, in which the flight conditionindicating instrument is an air speed indicator connected to theauxiliary lever.

3. The trainer defined in claim 1, in which the flight conditionindicating instrument is a rate-of-climb indicator connected to theauxiliary lever.

4. The trainer defined in claim I, in which the flight conditionindicating instrument is an altimeter connected to the auxiliary lever.

5. An aircrafi instrument operation trainer comprising a simulatedflight control including a shaft mounted for rotation and for lengthwisereciprocation, a tum-indicating instrument, and actuating means for saidturnindicating instrument including an elongated member extendingparallel to said shaft and held against lengthwise movement and a membermovable lengthwise of said elongated member by lengthwise movement ofsaid shaft and operable to move said elongated member transversely ofits length by rotation of said shaft in various lengthwise reciprocatedpositions of said shaft.

6. An aircraft instrument operation trainer comprising a simulatedflight turn control, a recording surface, steerable recording meansmovable over said surface, dogleg linkage carrying said steerablerecording means, orienting means carried by said dogleg linkage, drivemeans for efiecting movement of said recording means over said recordingsurface, and steering means actuated by said simulated flight turncontrol for driving said orienting means to alter the direction ofmovement of said recording means over said recording surface effected bysaid drive means.

7. The trainer defined in claim 6, further including an aircraftheading-indicating instrument, and instrumentactuating means operated bymovement of the recording means over the recording surface and operableto effect operation of the headingindicating instrument.

8. The trainer defined in claim 7, in which the heading-indicatinginstrument is an ADF instrument.

9. The trainer defined in claim 8, in which the instrument-actuatingmeans includes means operated by the simulated flight turn controlindependently of movement of the recording means over the recordingsurface.

10. The trainer defined in claim 8, in which the instrument is a VCRindicator.

11. The trainer defined in claim 10, in which the VCR indicator includesa shiftable to" and from" display and the instrument-actuating meansincludes means for shifting the display to alter the word displayed.

12. The trainer defined in claim 10, and manuallyoperable meansconnected to the instrument-actuating means for counteracting the effectof the recording means on e instrument-actuating means tending to effectoperation of the VCR indicator.

13. The trainer defined in claim 12, in which the instrument-actuatingmeans includes a cam member and a cam-follower member cooperating withsaid cam member, one of said members being movable by movement of therecording means over the recording surface and the other member beingmovable by the manuallyoperable means.

14. An aircraft instrument operation trainer comprising a simulatedflight turn control, a recording surface, steerable recording meansmovable over said surface, drive means for effecting movement of saidrecording means over said recording surface, steering means actuated bysaid simulated flight turn control for altering the direction ofmovement of said recording means over said recording surface effected bysaid drive means, a VCR indicator, instrument-actuating means operatedby movement of said recording means over said recording surface andoperable to effect operation of said VOR indicator, andmanually-operable means connected to said instrument-actuating means forcounteracting the effect of said recording means on saidinstrument-actuating means tending to effect operation of said VORindicator, said instrument-actuating means including a cam member and acam-follower member cooperating with said cam member, one of saidmembers being movable by movement of said recording means over saidrecording surface and the other member being movable by saidmanually-operable means.

I" i ll

1. An aircraft instrument operation trainer comprising a simulatedflight control, a simulated engine control, a flight conditionindicating instrument, and drive means connected to drive saidinstrument and including a main lever connected to said simulated flightcontrol and an auxiliary lever pivotally mounted on one arm of said mainlever at a location spaced from the rotative axis of said main lever,said auxiliary lever being connected to said simulated engine controlfor actuation of said instrument both by said simulated flight controland by said simulated engine control.
 2. The trainer defined in claim 1,in which the flight condition indicating instrument is an air speedindicator connected to the auxiliary lever.
 3. The trainer defined inclaim 1, in which the flight condition indicating instrument is arate-of-climb indicator connected to the auxiliary lever.
 4. The trainerdefined in claim 1, in which the flight condition indicating instrumentis an altimeter connected to the auxiliary lever.
 5. An aircraftinstrument operation trainer comprising a simulated flight controlincluding a shaft mounted for rotation and for lengthwise reciprocation,a turn-indicating instrument, and actuating means for saidturn-indicating instrument including an elongated member extendingparallel to said shaft and held against lengthwise movement and a membermovable lengthwise of said elongated member by lengthwise movement ofsaid shaft and operable to move said elongated member transversely ofits length by rotation of said shaft in various lengthwise reciprocatedpositions of said shaft.
 6. An aircraft instrument operation trainercomprising a simulated flight turn control, a recording surface,steerable recording means movable over said surface, dogleg linkagecarrying saId steerable recording means, orienting means carried by saiddogleg linkage, drive means for effecting movement of said recordingmeans over said recording surface, and steering means actuated by saidsimulated flight turn control for driving said orienting means to alterthe direction of movement of said recording means over said recordingsurface effected by said drive means.
 7. The trainer defined in claim 6,further including an aircraft heading-indicating instrument, andinstrument-actuating means operated by movement of the recording meansover the recording surface and operable to effect operation of theheading-indicating instrument.
 8. The trainer defined in claim 7, inwhich the heading-indicating instrument is an ADF instrument.
 9. Thetrainer defined in claim 8, in which the instrument-actuating meansincludes means operated by the simulated flight turn controlindependently of movement of the recording means over the recordingsurface.
 10. The trainer defined in claim 8, in which the instrument isa VOR indicator.
 11. The trainer defined in claim 10, in which the VORindicator includes a shiftable ''''to'''' and ''''from'''' display andthe instrument-actuating means includes means for shifting the displayto alter the word displayed.
 12. The trainer defined in claim 10, andmanually-operable means connected to the instrument-actuating means forcounteracting the effect of the recording means on theinstrument-actuating means tending to effect operation of the VORindicator.
 13. The trainer defined in claim 12, in which theinstrument-actuating means includes a cam member and a cam-followermember cooperating with said cam member, one of said members beingmovable by movement of the recording means over the recording surfaceand the other member being movable by the manually-operable means. 14.An aircraft instrument operation trainer comprising a simulated flightturn control, a recording surface, steerable recording means movableover said surface, drive means for effecting movement of said recordingmeans over said recording surface, steering means actuated by saidsimulated flight turn control for altering the direction of movement ofsaid recording means over said recording surface effected by said drivemeans, a VOR indicator, instrument-actuating means operated by movementof said recording means over said recording surface and operable toeffect operation of said VOR indicator, and manually-operable meansconnected to said instrument-actuating means for counteracting theeffect of said recording means on said instrument-actuating meanstending to effect operation of said VOR indicator, saidinstrument-actuating means including a cam member and a cam-followermember cooperating with said cam member, one of said members beingmovable by movement of said recording means over said recording surfaceand the other member being movable by said manually-operable means.